As a brand new Photoshop PM, one of my first trips was back to NYC to visit motion graphics artists. Touring one shop I was amazed to glimpse a technique I’d never seen, using Photoshop to break 2D photos into layers, fill in gaps, and then animate the results in After Effects. Later that year the work came to the big screen in The Kid Stays in the Picture, the documentary that now lends its name to this ubiquitous parallax effect.
Here Yorgo Alexopoulos talks about how he developed the technique & how he’s leveraged it in later works:
Below, artist Joe Fellows gives a brief, highly watchable demo of how it’s done (although it physically pains me to see him using the Pen tool to make selections & no Content-Aware Fill to at least block in the gaps):